Here is a shocking story about an academic who hasn't read a scholarly book outside her specialty since 1995. You have to think laterally to have a decent scholarly base. Imagine if I'd never read a work of art history or musicology or anthropology or philosophy in 15 years! I hope I'm interpreting this story wrong, but I don't even see how you could even do your own research without consulting books outside your narrow specialty. How could that not lead to tunnel vision? Of course, someone working in that mode is likely to produce scholarship that isn't of interest to anyone else eitherm thus perpetuating the cycle.
While I don't exactly approve of such a lack of curiosity, I do have my own limits as well. I'm sure I could develop a long list of things I haven't been curious about in the past 15 years - even if I think of myself as someone who is extremely curious about a wide range of subjects.
My sense is that we are less interdisciplinary than we think we are, if such stories are at all typical. Certainly if I had read so narrowly I would never admit to it.